Good day

I have a wAP ac with Model number RBwAPG-5HacT2HnD, which has 1 ethernet and two wlan interfaces: one for 2,4GHz and other for 5GHz.

I am doing a research project and for its needs my network should have separate IPs for 2.4 and 5 GHz channels so that following connection scheme could be implemented:

Desktop---Mikrotik eth1
Mikrotik wlan1 (2.4GHz) --- client 1
Mikrotik wlan2 (5GHz) --- client 2

I do not need Internet connection, just sending data over WiFi.

Currently the Mikrotik is in ap-bridged mode with all of its interfaces bridged. How do I configure it in such way that I can simultaneously send data from desktop over both wireless channels? I have been told that it is possible with NAT, but how exactly to implement this?

Thank You in advance

Try some better explanation. If you want to have one client connected to 5 GHz, another to 2.4 GHz, and communicate with both of them at the same time, it already works, doesn't it? Each one already has different IP address.